Bodyguard creator Jed Mercurio has defended the drama's sex scene after some viewers thought it was unnecessary to the plot.

The second episode of the BBC1 thriller features bodyguard David Budd (Richard Madden) and Home Secretary Julia Montague (Keeley Hawes) in an erotic scene.

Mercurio told the Press Association: "It's very important to their relationship... It creates a complication.

"It's not about the titillation of the sex scene," he said.

"It's about the fact that it complicates their relationship in a way which creates intrigue and possible bluffs and double bluffs and raises questions about their honesty towards each other."

The drama features intimate scenes between Julia Montague and younger man David Budd.

"I think we are all familiar with Hollywood casting, where you get a geriatric leading man and a nubile leading lady," Mercurio said.

"It's fine in a drama where that is part of the story and it's talked about and they're both aware of it and it influences how people see them as a couple.

"But when it's just presented as the norm that feels a little bit weird and creepy.

"In terms of the two leads in Bodyguard, yes the female is older than the male but also she is a much more powerful person in society and that's part of the tension in their relationship."

Mercurio dashed hopes that a second series was already in the works - saying that would be a decision for the BBC.

He said that airing the first two episodes consecutively was "purely the accident of choosing to broadcast starting at the Bank Holiday weekend" rather than a deliberate plan to mimic the success of sites like Netflix which stream a whole series at once.

And he teased of the next instalment: "What happens going forward is that this affair they have embarked on has put them both in a very tricky position.

"If that comes out, it could have dire consequences for both of them."

He added: "We are aiming to have more of the same, keeping it tense and thrilling and with really interesting relationships."